Rubber-covered article and method of making the same.



tween the rubber and the metal.

UNITED STATES PATENT OFFICE,

LEO DAFT, or RUTHERFORD, NEW JERSEY, AssIeNOn '10 nnncrno-cnnmcn'n RUBBER AND manurnc'ronme COMPANY, A CORPORATION on NEW JERSEY.

RUBBER-COVERED ARTICLE AND METHOD OF MAKING THE SAME.

No Drawing.

To all whom it may concern:

Be it known that I, LE0 DAFT, a subject of the King of Great Britain, and a resident of Rutherford, in the county of Bergen and State of New Jersey, have invented a of attaching the rubber are, as is well known, unsatisfactory by reason of the weakness of the bond between the rubber and the metal, making them liable tO- separation at the point of juncture.

By means of my improved method I am enabled to produce a perfect adhesion be- In this manner a bond is produced between the rubber and the metal which is as strong as, or stronger than the neighboring parts of the rubber and will therefore not loosen. My improved method consists essentially in heating the rubber while in contact with metal containing an alloy of antimony. In practising this method the rubber may be heated while in direct contact with a metal base or article provided that base or article is an alloy of antimony or if such metal base or article is not such an antimony alloy'and therefore has not the proper surface, then a surface of an alloy, of antimony is first applied to such metal base or article, preferably by electro-plating, as hereinafter described and the rubber is then heated while in contact with said coated surface.

commercial rubber and the 1 metal alloy are- "These proportions. are suitable Specification of Letters Patent.

Patented Dec. '15, 1914.

Appli pation filed June 3, 1910. Serial Ne. 564,840.

. grades of commercial rubber containing five per cent. of sulfur or an equivalent in the form of sulfids but, however, are not exact for all grades of rubber, for, when the rubber contains a relatively large amount of sulfid of antimony, the amount of antimony contained in the alloy may be proportionately decreased.

My method may be carried but as fol lows: YV hen the metal base to which the rubber 1s to be attached is itself an alloy of antimony, the surface of the base or'article should be first thoroughly cleaned by means of emery wheels or by any other suitable method. The rubber is then brought into d1rect contact with the surface of this metal alloy base or article and placed in a vulcanizer and vulcanized to it at a high temperature, say, 245 to 300 degrees Fahrenheit. This heating vulcanizes the rubber and produces a strong bond between the alloy and the rubber. When, however, it is impracticable to form the base, to the surface of which the rubber is to be attached, of an alloy of antimony, as, for instance, by casting, I confer upon such base or article a surface of an alloy of antimony and attach the rubber to that surface in the same manner as to the surface of a base or article of the antimony alloy itself. This may be most conveniently done by electro-plating the base or article to which the rubber is to be attached with an' alloy of antimony. The electro-plating may be done by any suitable method. In

the practice of my invention I prefer to ro- Sodium carbonate 10 oz. Sodium bisulfid 10 Copper carbonate 3J Zinc carbonate 3% M Antimony chlorid .1} Water 32O Potassium cyanid,a quantity sufficient to, dissolve theprecipitate. 1 The base or article" to be plated is-placed in this bath and electroplated at a potensurface of sufiicient thickness of the alloy. of antimony shall have been deposited 'ti al of approximately 2 to 3% volts, until a Another plating bath which I find to give good results is compounded in the following manner: I dissolve 15% ounces of sodium carbonate in 5 quarts of water and dissolve 5i ounces-of copper sulfate and 55; ounces of zinc sulfate in 5 quarts of water. I then mix these two solutions together, thus producing a precipitation of copper and zinc carbonate. I then add a solution obtained by dissolving half an ounce of metallic antimony in hot sulfuric acid (specific gravity 1.800) and precipitating with an excess of ammonium sulfid. After the precipitate has settled I pour off the clear fluid and add about 6 quarts of water to the precipitate and then gradually add 7 ounces of sodium carbonate and 7 ounces of soda bisulfid. I then add 8% .ounces of potassium cyanid and clear the bath with 30 grains of arsenious acid dissolved in 10 ounces of water. This bath is used in the same manner as that described above.

Still another method of plating a surface upon the base or article to which rubber is to be attached, is by the use of a transfer solution containing the following ingredients:

Crystal soda bisulfid 14% oz. Crystal ammonium chlorid 92 Potassium cyanid 2% Water 10 qts.

When using these baths I prefer to use an anode made of an alloy containing the same propprtions of copper, zinc and antimony as a ove referred to, viz:

Copper--. 32,- lbs. Zinc 1% Antimony 3 oz.

It will be noted that the first two baths referred to contain the salts of copper, zinc and antimony, while the last of the abovementioned baths is strictly a transfer solution in which the metals are transferred from the anode to the bath and from the bath to the article to be plated.

All of the methods of electro-plating which I have thus far described can be used where the base or article, to the surface of which the rubber is to be attached, does not contain copper and zinc, but when it is desired to practise my invention upon a metal base or article which already contains copper and zinc, such as brass or bronze, then the electro-plating bath may consist of antimony without co per or zinc in solution. In this case I pre er to use a. bath composed of the sodium salt of sulfantimonic acid (commonly known as' Schlippes salt) in the proportion of 1% ounces-of the salt to 35 ounces'of water.v Electra-plating for a very short time in this bath is sufiicient. It will be obvious that in this case the anode need not be of antimony, zinc and copper, and when using this solution I preferably precise proportions of the various ingred1- ents set forth above, nor to the use of the identical ingredients themselves, as many of them have well known chemical equivalents. Nor do I intend to confine myself to the exact method described of causing the rubber to adhere to the metal, it being evident that all of these may be varied within relatively wide limits without departing from the spirit of my invention. In my co-pending application No. 605,170, I have described and claimed another method of electro-plating which may be used in practising the invention described and claimed herein.

What I claim and desire to secure by Letters Patent of the United States is:

l. The method of attaching rubber to metals, which consists in depositing an antimony alloy upon the surface of the metal, bringing rubber containing a vulcanizing agent into engagement with the surface thus treated, and vulcanizing said rubber upon said surface.

2. The method of attaching rubber to metals, which consists in depositing antimony and copper upon the surface of the metal, bringing rubber containing a vulcanizing agent into engagement with the surface thus treated, and vulcanizing said rubber upon said surface.

3. The method of attaching rubber to metals, which consists in depositing upon the surface of the metal to be treated an alloy of copper, zinc and antimony, bringing rubber containing a vulcanizing agent into engagement with said alloy, and vulcanizing said rubber upon said alloy.

4:. A new article of manufacture, consisting of a metal base having a non-stannous surface formed thereon and containing antimony, copper and zinc with a rubber covering vulcanized thereon.

5. The method of attaching rubber to metals which consists in depositing antimony upon the surface of the metal by electro-deposition, bringing rubber containing a vulcanizing agent into engagement with the surface thus treated and vulcanizing the rubber upon said surface.

6. The method of attaching rubber to metals which consists in depositing an antimony alloy upon the surface of the metal by elec tro-deposition, bringing rubber containing a vulcanizing agent into engagement with the surface thus treated and vulcanizing the rubber upon said surface.

7. The method of attaching rubber to metals which consists in electroplating the metal in an electrolyte containing antimony and copper, obtaining a deposit containing antimony and copper, bringing rubber c0n'- 136 tainin a vulcanizing agent into engagement with t e surface thus treated, and vulcaniz- -ing said rubber upon said surface.

base of an alloy copper and zinc a solution of Schlippes salt, bringing rubber containing a vulcanlzing agent into contact 15 with the surface thus formed and vulcanizing the rubber to the surface.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

- LEO DAFT.

Witnesses:

WALTON HARRISON, PHILIP D. ROLLHAUS. 

